Without question, Shawne Williams wants to return to the Knicks next year.

Williams will be a free agent this summer, and the valuable forward was perhaps the Knicks’ most pleasant surprise of the season. The four-year veteran didn’t play in the NBA last season, earned a spot on the Knicks’ roster in training camp, didn’t get off the bench in the first 17 games, then emerged as a key reserve and spot starter.

“This is where I want to play at,” Williams said. “Great group of guys. A couple great superstars that I feel like we can do something with.”

Knicks president Donnie Walsh drafted Williams in 2006 when he ran the Pacers. The promising Williams had a rocky NBA career, however, with troubles including two arrests for drugs, a 2008 trade to Dallas (where he clashed with owner Mark Cuban) and a subsequent deal to the Nets in January of last year. The Nets waived Williams four days later. He signed with the Knicks last September.

The 25-year-old Williams — who has the same agent, Happy Walters, as his friend and teammate Amar’e Stoudemire — averaged 7.1 points and 3.7 rebounds this season while shooting an impressive 40.1 percent from 3-point range, 30th in the league.

“I feel like I’ve defined my role with this team a little bit,” Williams said of his long-range touch. “But I can do a little bit better.”

In his first career postseason, Williams has averaged 8.3 points in three games against the Celtics, including a Knicks-high 17 points on 6-for-10 shooting in Friday’s 113-96 loss at the Garden. He added six rebounds and two steals that night as well.

If the Knicks don’t win Game 4 today, however, it could be Williams’ final game with the team.

“It’s really not time to think about that right now. But it’s a possibility. That’s reality,” said the 6-foot-9, 235-pounder. “I’m going to leave [my future] up to my agent. When it’s time to sit down and talk about that, we’re going to talk about it.”